The Syrian government has warned protesters in the city of Homs to stop demonstrations , hand in weapons and surrender defecting military members by Monday night or face bombardment , an opposition leader said .

A 72-hour warning was given Saturday , said Lt. Col. Mohamed Hamdo of the Free Syrian Army . Activists on the ground said the ultimatum was issued on Friday .

The Syrian National Council , the country 's leading opposition movement , had warned earlier of a potential bloodbath at the hands of the Syrian regime in Homs .

`` If the world continues to watch , then the massacre of Hama in the '80s will be repeated , '' said Hamdo , referring to 1982 , when Syria 's military -- acting under orders from current President Bashar al-Assad 's father , Hafez al-Assad -- launched an assault on the city , killing thousands .

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The military has dug trenches around Homs , Hamdo said .

`` There is no electricity , water , or communication whatsoever now and the communication breakdown has extended even closer to the Turkish border , '' he said .

The Syrian government denied reports of water and electricity being out in the city , according to the state-run Syrian Arab News Agency -LRB- SANA -RRB- .

The government made no mention of the reported deadline on the news agency 's website Sunday morning .

Opposition figures launched a nationwide anti-government strike Sunday , which they called the `` strike of dignity . ''

The London-based Syrian Observatory for Human Rights , which gets information from people in different parts of the country , said people in Homs and neighboring towns widely joined the strike . `` All shops were closed on all main roads in the city , '' the group said .

Several videos posted on Youtube purported to show government loyalists breaking locks of shops that closed in support of Sunday 's anti-government strike .

But on SANA , the Syrian government quoted people across the country as saying there was no strike and no sign of a strike . `` It was a normal trading day in markets throughout the Syrian provinces as people bought and sold consumer goods , vegetables , fruit and clothes as economic elements shrugged off all inflammatory tendentious calls by terrorist groups that are associated with foreigners , '' the government insisted .

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As violence raged Sunday in parts of the country , the death toll reached 23 , according to the opposition Local Coordination Committees of Syria -LRB- LCC -RRB- . Five of the dead were children , the group said .

The toll includes six people in Hama ; six in Homs ; five in Idlib ; three in suburbs of Damascus , and three in Daraa , according to the LCC , a network of anti-regime activists in the country .

One of the deaths in the Daraa area took place in Jasem , where a man was arrested and then returned to his family dead after about three hours , the LCC said .

In the city of Aleppo , security forces burned down a factory in an industrial area that was participating in the strike , the LCC said .

SANA , meanwhile , reported that the `` bodies of 13 martyrs from the army , security and police forces '' were taken `` to their final resting place . '' Four were from Homs .

Authorities in Homs arrested `` armed men who tried to impose an obligatory sit-in '' and who shot at people in cars and streets , SANA said .

CNN can not independently confirm events because the Syrian government restricts access of international media to the country .

The Syrian government said authorities in Idlib `` confronted members of an armed terrorist group '' who were blocking a road and `` killed and injured a number of its members . '' Authorities also chased another `` armed gang '' and killed two of its members , SANA said .

In Hama , Syria said , officials arrested `` a member of armed terrorist groups '' who was trying to plant an explosive device near residential buildings . SANA said the military dismantled the bomb and no one was injured .

Throughout the Syrian uprising , government officials have described some opposition fighters as armed terrorists and gang members .

There were clashes Saturday in Khan Sheikhon , where authorities `` arrested a number of the terrorists and killed three of those groups ' prominent leaders , '' SANA said in a report Sunday .

In the city of Kfar Takharim , `` a number of the members of armed terrorist gangs were killed or injured in clashes with the authorities on Saturday evening , '' SANA said , adding that one member of the authorities was killed and six others were injured .

Fierce clashes were underway Sunday in the Daraa Province village of Busra al-Harir as Syrian troops battled defectors , leaving many people wounded , according to the Syrian Observatory for Human Rights .

Residents said members of Syria 's 12th Armored Brigade , which is based near the border with Jordan , `` stormed '' Busra al-Harir . They said they heard explosions and heavy gunfire in the city and just north of it in Lujah , where defectors were believed to be hiding , the observatory said .

Security forces in Idlib were using mosque speakers to threaten residents to end their strike and to force people to reopen businesses , the observatory said , citing eyewitnesses .

The Arab League announced it will hold emergency meetings this week in Cairo . In a statement on Egypt 's state-run MENA news agency , an Arab League official said leaders will `` discuss the Arab response to a message from Syrian Foreign Minister Walid Moallem to approve the signing of an agreement on an Arab League observing mission to Syria with conditions . ''

World leaders have widely condemned Syria 's crackdown and called on it to halt violence against the opposition .

On Saturday , France expressed its concerns about events in Syria , and warned against Syria launching a military operation against the city of Homs and its population , the French Foreign Ministry said in a statement .

Al-Assad 's regime has denied targeting peaceful protesters .

The regime 's actions have outraged world powers and sparked sanctions by the Arab League , Turkey , the United States and the European Union .

Israeli President Shimon Peres on Sunday described Syrian President al-Assad as a `` killer , '' implicitly comparing him to Libya 's ousted ruler Moammar Gadhafi .

`` The world decided -- including the Arab world -- to intervene when a leader is beginning to kill his own citizens , '' Peres told CNN in an interview . `` It happened in Libya ; it 's happening in Yemen ; it 's happening by the Arab League , for the first time in their experience . They decided to put pressure on an Arab state because the leader is killing his people . ''

The United Nations said this month that more than 4,000 people have died in Syria since the crackdown began in mid-March .

Protesters have been demanding the end of the al-Assad regime and democratic elections . Al-Assad has been in power since 2000 ; his father , Hafez , ruled Syria for three decades .

Local elections are set to take place Monday for municipal posts .

In its 2010 Human Rights Report about Syria , the U.S. State Department said Syria 's elections have not been fair in the past .

`` Although the constitution provides the right for citizens to peacefully change their government through elections , in practice they did not have that right because elections were neither free nor fair , '' the report said .

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Residents of Homs widely participate in Sunday 's national strike , an opposition group says

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Syrian state media quotes people saying there is no strike

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23 people were killed Sunday , an opposition group says

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Syria says it killed `` terrorists '' in Idlib